If you live in these parts, you have probably been to San Francisco, seen the Golden Gate Bridge, and visited Pier 39 already.
Here are some suggestions for outings that can take only half a day and are also good places if your visitors are staying for a longer period of time.
For trips that require some driving, look under the California location. Naturally there are many other places, but we have found some that are not generally known among foreigners.
Regardless where you go in nature, remember to bring drinking water. The air is dry and you don't feel how much you sweat. Children (and grandparents) can get dehydrated and cranky(confused) amazingly fast.